In this article I will explain with an example, how to resolve the following error: 
Access denied for user 'roots'@'localhost' (using password: YES)  while working with 
MySQL database.
 
     
    Error
    This error occurs due to the following reason in 
MySQL database.
1. User Id or Password specified in connection string is not correct.
    ![MySqlException: Access denied for user 'roots'@'localhost' (using password: YES) error in MySql Database]() 
     
    In the below connection string, the User Id and Password are incorrect.
    
        <connectionStrings>
            <add name="constr" connectionString="Data Source=localhost;port=3306;Initial Catalog=Northwind;User Id=roots;password=pass@1234" />
        </connectionStrings>
     
     
     
    Solution
    Following is the solution for the above error.
    1. Make sure that the User Id and Password are correct in the connection string as shown below.
    
        <connectionStrings>
            <add name="constr" connectionString="Data Source=localhost;port=3306;Initial Catalog=Northwind;User Id=root;password=pass@123" />
        </connectionStrings>